Apparatus including a radiation source, a filter system for filtering particles out of radiation emitted by the source, and a processing system for processing the radiation, a lithographic apparatus including such an apparatus, and a method of filtering particles out of radiation emitting and propagating from a radiation source

Abstract

Particles emitted by a radiation source, and moving from the radiation source towards a processing system for processing the radiation from the radiation source, are filtered out of radiation propagating through a predetermined cross section of the radiation as emitted by the radiation source by a filter system. The filter system includes a plurality of foils and a transporter for transporting the foils along a trajectory which extends within the beam so that the foils intercept the particles within the beam. The transporter is arranged to transport the foils by a substantially translatory movement of the foils along at least a part of the trajectory.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a method for filtering particles out of a beam of radiation propagating from a radiation source towards a processing system, a filter system, an apparatus and a lithographic apparatus including the filter system.[0003]2. Description of the Related Art[0004]A lithographic apparatus is a machine that applies a desired pattern onto a substrate, usually onto a target portion of the substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In that instance, a patterning device, which is alternatively referred to as a mask or a reticle, may be used to generate a circuit pattern to be formed on an individual layer of the IC. This pattern can be transferred onto a target portion (e.g. including part of one or several dies) on a substrate (e.g. a silicon wafer). Transfer of the pattern is typically via imaging onto a layer of radiation-sensitiv...

AI Technical Summary

Benefits of technology

[0008]It is an aspect of the present invention to provide an apparatus including a radiation source, a processing system configured to process the radiation from the radiation source and a filter system configured to reduce the number of particles traveling away from the radiation source that reach the processing system, wherein the filter system provides for more freedom of design in positioning the filter system with respect to the radiation source as compared to filter systems known in the prior art.

[0013]In each of the above aspects of the present invention the foils or plates are transported in a substantially translatory movement along at least a part of the trajectory which extends within the beam. Incorporating the translatory movement of the foils allows the design of a multitude of possible trajectories. Hence the design of the trajectory can be chosen such that the design of the filter system can easily be adapted to dimensions and / or arrangements of the radiation source and / or processing system.

Problems solved by technology

Plasma radiation sources, however, besides EUV radiation, often generate debris.

Part of the rotation unit blocks part of the radiation from entering the optical system, e.g. thus reducing the radiation transferring efficiency of the debris removing system Furthermore the attracting unit occupies a large volume close to the radiation source, so that placement of the debris removing system becomes difficult and / or the volume available for the radiation source is limited.

Images